Wu Haibin, Qin Jinxia, Han Jun, Zhao Xiaojie, Ouyang Shuhong, Liang Yong, Zhang Dong, Wang Zhenzhong, Wu Qiuhong, Xie Jingzhong, Cui Yu, Peng Huiru, Sun Qixin, Liu Zhiyong
State Key Laboratory for Agrobiotechnology / Beijing Key Laboratory of Crop Genetic Improvement / Key Laboratory of Crop Heterosis Research & Utilization, Department of Plant Genetics & Breeding, China Agricultural University, Beijing, China.
State Key Laboratory for Agrobiotechnology / Beijing Key Laboratory of Crop Genetic Improvement / Key Laboratory of Crop Heterosis Research & Utilization, Department of Plant Genetics & Breeding, China Agricultural University, Beijing, China ; Plant Science and Technology College, Beijing University of Agriculture, Beijing, China.
PLoS One. 2013 Dec 23;8(12):e84691. doi: 10.1371/journal.pone.0084691. eCollection 2013.
The wax (glaucousness) on wheat leaves and stems is mainly controlled by two sets of genes: glaucousness loci (W1 and W2) and non-glaucousness loci (Iw1 and Iw2). The non-glaucousness (Iw) loci act as inhibitors of the glaucousness loci (W). High-resolution comparative genetic linkage maps of the wax inhibitors Iw1 originating from Triticum dicoccoides, and Iw2 from Aegilops tauschii were developed by comparative genomics analyses of Brachypodium, sorghum and rice genomic sequences corresponding to the syntenic regions of the Iw loci in wheat. Eleven Iw1 and eight Iw2 linked EST markers were developed and mapped to linkage maps on the distal regions of chromosomes 2BS and 2DS, respectively. The Iw1 locus mapped within a 0.96 cM interval flanked by the BE498358 and CA499581 EST markers that are collinear with 122 kb, 202 kb, and 466 kb genomic regions in the Brachypodium 5S chromosome, the sorghum 6S chromosome and the rice 4S chromosome, respectively. The Iw2 locus was located in a 4.1 to 5.4-cM interval in chromosome 2DS that is flanked by the CJ886319 and CJ519831 EST markers, and this region is collinear with a 2.3 cM region spanning the Iw1 locus on chromosome 2BS. Both Iw1 and Iw2 co-segregated with the BF474014 and CJ876545 EST markers, indicating they are most likely orthologs on 2BS and 2DS. These high-resolution maps can serve as a framework for chromosome landing, physical mapping and map-based cloning of the wax inhibitors in wheat.
小麦叶片和茎上的蜡质（白粉）主要由两组基因控制：蜡质基因座（W1和W2）和无蜡质基因座（Iw1和Iw2）。无蜡质（Iw）基因座作为蜡质基因座（W）的抑制剂。通过对与小麦Iw基因座同线区域相对应的短柄草、高粱和水稻基因组序列进行比较基因组学分析，构建了源自野生二粒小麦的蜡质抑制剂Iw1和节节麦的Iw2的高分辨率比较遗传连锁图谱。开发了11个与Iw1连锁的EST标记和8个与Iw2连锁的EST标记，并分别定位到2BS染色体和2DS染色体远端区域的连锁图谱上。Iw1基因座定位在一个0.96 cM的区间内，两侧分别是BE498358和CA499581 EST标记，它们分别与短柄草5S染色体、高粱6S染色体和水稻4S染色体上的122 kb、202 kb和466 kb基因组区域共线。Iw2基因座位于2DS染色体上4.1至5.4 cM的区间内，两侧是CJ886319和CJ519831 EST标记，该区域与2BS染色体上跨越Iw1基因座的2.3 cM区域共线。Iw1和Iw2均与BF474014和CJ876545 EST标记共分离，表明它们很可能是2BS和2DS上的直系同源基因。这些高分辨率图谱可作为小麦蜡质抑制剂染色体着陆、物理图谱构建和基于图谱的克隆的框架。
